1. Field of the Invention
This invention relates to an image scanning system for scanning a light beam to record an image or to read a recorded image, and more particularly to an image scanning system in which the main scanning of the light beam is effected by deflecting the light beam across a recording medium using an optical deflector and the sub-scanning is effected by mechanically moving the recording medium.
2. Description of the Prior Art
In an image recording system or an image reading system in which a light beam emitted from a light source is guided to a recording medium by way of optical systems such as optical deflectors and mirrors, turbulence in the image scanning is apt to occur because of minute displacements of the optical components which are amplified by the optical lever effect. These displacements of the optical components are generated by external forces due to forced vibrations from various actuators inside the system and/or from outside. In order to reduce the influence of the external forces, various remedies have been used. For example, conventional remedies include providing each actuator with an antivibration device, increasing the rigidity of the overall system and controlling the operating sequence to make the actuators inoperative while the scanning is being effected. Conventional remedies for eliminating vibrations from outside the system include placing the overall system on an antivibration platform and fixing the overall system on a large base.
The conventional remedies are disadvantageous in that in the case of a system provided with devices for feeding recording media thereto and discharging them therefrom, the overall system becomes complicated and the manufacturing cost thereof is significantly increased. For example, if each actuator is provided with an antivibration device or the rigidity of the frame is increased, the manufacturing cost of the system or the weight of the overall system is directly increased. If the operating sequence is arranged to make the actuators inoperative while the scanning is being effected, the cycle time of the system is lengthened and the efficiency of the system is lowered.